Bioethicist Art Caplan, Director of the Center for Bioethics at the University of Pennsylvania, has bet Republican presidential candidate Michele Bachmann $10,000 that she cannot prove her claim that the HPV vaccine causes mental retardation.

Bachmann chastised Texas Governor Rick Perry during the Sept. 12 Republican debate for requiring girls in his state to get the HPV vaccine, which prevents a sexually transmitted virus that causes cancer. The next day in television interviews, Bachmann said a woman told her that the HPV shot caused mental retardation in the woman’s daughter.

Caplan said the statements by Bachmann may cost lives by frightening parents from vaccinating their daughters. He said he’ll pay $10,000 to Bachmann’s charity of choice if she can find such a patient.

Caplan said today in an interview: “It’s ethically obscene. The stakes are too high to try to get political advantage by putting young women’s lives at risk.”

If Bachmann takes the challenge and is unable to find three reputable doctors who agree a girl was made mentally retarded by Gardasil, she will have to pay $10,000 to Caplan’s charity of choice, he said.

Caplan announced the wager on Twitter, but hasn’t heard from the Bachmann campaign.